> For the complete documentation index, see [llms.txt](https://docs.pentaho.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pentaho.com/pdc-10.2-data-optimizer/pdso-install-landing-page/pdso-install-in-hadoop-cluster/pdso-maintain-landing-page/pdso-maintain-data-optimizer-metadata-cp.md).

# Maintain Data Optimizer metadata

Each Pentaho Data Optimizer volume maintains an authoritative local data store that contains the metadata of all files and directories stored by the instance. The term “authoritative” means that the metadata in the store is complete, current, and trusted. The authoritative local metadata store gives significant performance benefits, allowing the Data Optimizer volume to handle metadata inquiries internally without making external API calls to the S3 storage device.

If the local metadata store for a Data Optimizer volume becomes lost or corrupted, you need to recover the metadata store. For example, corruption might occur if the metadata is stored on a failed disk drive. Recovering the store involves relocating the store, putting the Data Optimizer volume in recovery mode, and running the recovery procedure.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.pentaho.com/pdc-10.2-data-optimizer/pdso-install-landing-page/pdso-install-in-hadoop-cluster/pdso-maintain-landing-page/pdso-maintain-data-optimizer-metadata-cp.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.